In the manufacture of many finished textile products, there is occasion to maintain together a number of textile blanks in a web form, and then after treatment of the blanks in the web form to separate them from each other before they are made into a final textile article. The textile blanks are typically connected together by what is commonly referred to as "connector threads" or "separation yarns". The connector threads connect adjacent blanks to each other in such a way that they can be commonly treated together as a web, but so that after a connector thread is severed it may be easily unravelled to thereby effect separation of the textile blanks.
One particular procedure in which textile blanks are commonly maintained together during treatment and subsequently separated is called for in the manufacture of collars for knit sport shirts. After each collar is knitted, and knitted to an adjacent collar with a connector thread, the web of collars is washed, dyed and finished. It is then necessary to effect separation of the collars from each other before sewing them into the final sport shirt. Commercially, this is typically done by hand or in a semi-automatic manner, in which an operator cuts one portion of the connecting thread with a scissors or a hot wire cutter, grabs the connector thread and completely unravels it, or grabs the connector thread and moves it into operative association with a rotating element which then completes the unravelling operation. Due to highly varying production schedules, it is extremely difficult to schedule personnel efficiently to perform the manual operations. Therefore, it is highly desirable to be able to completely automate the textile blanks separating procedure, such as during the manufacture of collars for knits sport shirts.
According to one aspect of the present invention, apparatus is provided for effecting automatic separation of textile blanks connected by a connector thread. The basic components of the apparatus include a structure for moving the textile blanks to a predetermined position, a structure for severing the connector thread at that position, and a structure for automatically grasping the severed connected thread and effecting automatic unravelling of it.
The preferred structure for advancing the textile blanks into a desired position, according to the present invention includes a presser foot and a horizontal support surface. The textile blanks lie on the support surface with first and second edges thereof in a second dimension, generally perpendicular to a first dimension in which the connector thread extends. The presser foot is automatically moved downwardly into contact with a textile blank to press it against the support surface, and then it is moved in the second dimension to slide the textile blanks along the support surface to the desired first position. The fact that the textile blanks have moved to the desired first position is sensed by a photoelectric sensing system, and then a mechanical cutter is automatically actuated to effect severing of the connector thread along a first edge of the blanks.
Substantially simultaneously with the cutting of the connector thread along the first edge of the blanks, a loop of the connector thread is automatically grasped along the second edge of the blanks. It is difficult to be able to automatically grasp a connector thread, and that is a primary reason why prior art systems have required an operator to grab the thread with her/his fingers. However, according to the present invention, the thread is effectively automatically grasped by a pair of brushes which are mounted on a scissors linkage.
The brushes are pivotted into engagement with each other whereby the grasped connector thread between them, and the scissors linkage, is moved in the first dimension away from the support surface. This starts the unravelling process. After the connector thread has been unravelled a small amount, the scissors linkage moves the brushes away from each other whereby the connector thread is released. While the brushes have been moving away from the support surface, a hook has been automatically moved up into a position between the support surface and the brushes, and the hook engages the connector thread after it is released. The hook moves the connector thread through a yarn sensor and then past a pair of rollers, one having a stationary axis and the other having a moveable axis. Once the thread is moved past the rollers, the moveable axis roller moves into operative association with the stationary axis roller to thereby engage the thread and to effect complete unravelling thereof. An air jet, vacuum source, or the like operatively engages the thread after it has been unravelled by the rollers, and moves it to a disposal site.
According to another aspect of the present invention, there is provided a method for automatically separating textile blanks, such as knit sports shirt collars. In the practice of the method, the textile blanks are operatively engaged and automatically moved into a first position. At the first position automatically and substantially simultaneously a connector thread is severed adjacent one edge of the blanks, and grasped adjacent the other end of the blanks. The grasped portion of the connector thread is automatically moved in the first dimension, away from the blanks, and then it is automatically engaged and unravelled completely, and disposed of.
It is a primary object of the present invention to provide an effective apparatus and method for automatically separating textile blanks which are connected together by connector thread. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.